This invention concerns an integrated interface circuit between a television receiver and its peritelevision connector, to allow the connection of an external source such as a magnetoscope.
Such circuits, usually constructed from discrete components, are used for the selection of different audio and video tracks, either from a black-and-white or colour television receiver, or from an external source, such as a magnetoscope.
This invention proposes an integrated circuit comprising, in a single circuit, all the stages needed for an effective interface between the television receiver and its peritelevision connector. This considerably reduces the space required, compared with circuits known in the prior art, as well as providing a much better layout inside the receiver, since the peritelevision connector is attached and close to the switching unit. Such a circuit also has the advantage of being much cheaper to produce than existing circuits.
This new integrated interface circuit between a television receiver and its peritelevision connector, for the connection of an external source, such as a magnetoscope, comprises, within a single circuit, a video interface stage, an audio interface stage, and a switching stage, which uses logic signals at its inputs to switch or not switch, on the one hand a selector switch in the video stage, in order to select either the internal video signal from the television receiver, or the external video signal from the external source, and on the other hand selector switches in the audio stage, in order to select either the internal audio signal from the television receiver, or the external audio signal from the external source.
Other benefits and features of the invention will be made clear in the following description of one of many possible embodiments of the invention, illustrated by the accompanying FIGURE, showing the interface circuit in diagrammatical form.